1. Field of Invention
The present invention relates generally to the field of networks and pertains more particularly to a system for and method of sending network problem information along a communication path of a network having an unknown configuration and inaccessible components to reduce network problems.
2. Discussion of the Prior Art
Since at least as early as the invention of the first computer system, people have endeavored to link computers together. Linking computers together in a network allows direct communication between the various points of the network and sharing of resources among the points of the network. This was especially desirable early on because computers were very large and very expensive. Today, computers are far more prevalent, but the desire to link them together is still strong. This is most readily demonstrated by the explosive growth of the Internet.
Servers are commonly employed for sharing of information among large numbers of computer systems or similar devices. A computer system or similar device that communicates with a server is usually referred to as a client of the server and the server is often part of a host system. A client and a host typically exchange messages via a communication network using a predetermined protocol. Such protocols are usually arranged in a client/host model in which a requesting client transfers a request message to a host and the host in turn takes an appropriate action depending on the content of the request. Typically, the appropriate action for the request includes the transfer of a response message to the requesting client.
In an effort to conserve resources, networks are designed such that they do not generally consist of dedicated paths from every point in the network to every other point in the network. Rather, source points are connected to central switching points where messages are routed to the appropriate destination points. Although reducing the resources needed, switched networks do require monitoring and regulation to assure fair sharing of the network resources. Many problems may arise with the network that impact on the fair sharing of the resources. One problem, for example, that networks can suffer from is congestion. Monitoring of a network is performed by a detector which examines the messages that pass through it to spot signs of congestion. Congestion may result from a client who is generating too many messages, a switching point which is overloaded, or a server which is processing too few messages. One of ordinary skill in the art will realize that other signs and forms of congestion also exist. Regulation of a network is performed by a controller which acts to reduce congestion. The controller may routinely be an active participant in the handling of messages in the network or the controller may only monitor network traffic without handling the communication of messages. To reduce congestion, the controller may act alone, may act in concert with another device, or may direct another device to act on behalf of the controller. Congestion may be reduced by restricting the number of messages accepted from a client, routing messages through another switching point, or restricting the number of messages transmitted to a server. One of ordinary skill in the art will realize that other ways of reducing congestion also exist.
Traditionally, in order for network monitoring and regulation to be totally effective, knowledge of and control over all of the points in the network is necessary. This is not a problem if the network is owned by a single entity. However, if the network includes points along a path that are owned by more than one entity, then these requirements are missing and effective monitoring and regulation are severely limited. For example, even though a detector may recognize that the network is congested, the detector does not know how to inform the appropriate controller to relieve the congestion and the controller does not realize that there is a problem that it could address. This is especially the case for the Internet where multiple entities are involved including client web browsers, internet service providers, and web servers. The Internet is a patchwork of privately and publicly owned sub-networks without any centralized administration. Each of the sub-networks carries its own traffic, sends traffic to other sub-networks, receives traffic from other sub-networks, and may act as a relay to traffic that is just passing through. When congestion occurs there is a problem of knowing who to inform in order to reduce or eliminate the traffic at its source. Ideally, any excess traffic to a congested web site would be stopped before it even entered the network.
A definite need exists for a system having an ability to alleviate problems in a network having an unknown configuration and inaccessible components. In particular, a need exists for a system which is capable of sending network problem information along a communication path. Ideally, such a system would operate by observing a network problem and relieving it. With a system of this type, problem information would provide a reliable means of fairly sharing network resources. A primary purpose of the present invention is to solve this need and provide further, related advantages.
A system for and method of sending network problem information along a communication path of a network having an unknown configuration and inaccessible components is disclosed including a first device for observing network problems and a second device for relieving network problems. Upon observation of a problem, the first device generates and sends an enhanced loopback test message to the source of the problem. The enhanced loopback test contains information regarding the source and the nature of the problem. The second device, being along the path of the loop between the first device and the source, receives the problem information and responds by reducing the problem as appropriate.